Although not exclusively so, this type of wiper system is intended to equip a motor vehicle, notably to enable wiping of the windows thereof.
Motor vehicles are routinely equipped with windscreen wiper systems for washing the windscreen and preventing disruption of the driver's view of their environment. These windscreen wipers are conventionally driven by a wiper arm effecting a to-and-fro angular movement and include elongate wipers in turn bearing wiper blades made from an elastic material. These wiper blades rub against the windscreen and remove water the driver's field of view.
The wipers are produced either in the standard form of articulated wiper arms that hold the wiper blade at a plurality of discrete locations or more recently in a so-called “flat blade” version as a semi-rigid assembly that holds the wiper blade over all its length.
In each of these two versions, the wiper is attached to the pivoted wiper arm of the windscreen wiper by an assembly consisting of:                an end fitting, which extends the wiper arm at its upper end,        a mechanical connector, fastened to the wiper (crimped onto the wiper arm or directly onto the flat wiper), and        an adapter, which is an intermediate part for fixing the mechanical connector to the end fitting and therefore to the wiper arm.        
To fix the adapter into the end fitting it is already known to equip said adapter with at least one locking member fixed at the end of a flexible tongue, this locking member being able to cooperate with a complementary portion of the end fitting.
The documents U.S. Pat. No. 6,681,440, U.S. Pat. No. 7,669,276 and U.S. Pat. No. 7,621,016 disclose such adapters for wiper systems fastened to the mechanical connector by means of locking members fixed to the end of flexible tongues.
In the document U.S. Pat. No. 6,681,440 a locking member is disposed in the lower portion of the adapter and includes a projection relative to the flexible tongue to which it is fixed so that this projection can form an abutment for the complementary portion of the end fitting. However, in this prior art embodiment, the use of a single locking member makes it difficult to establish the connection between the adapter and the end fitting.
In the documents U.S. Pat. No. 7,669,276 and U.S. Pat. No. 7,621,016, two projections are provided on one side of the adapter, disposed on the lateral walls thereof, with two locking members on the other side of said adapter fixed to the end of flexible tongues and disposed on respective lateral walls of said adapter. However, in these prior art embodiments, the two locking members being disposed one facing the other, relative to the lateral walls of the adapter, the latter can be moved by deformation of their respective flexible tongues over only a short distance. It follows that manipulating these two locking members is difficult and that, in fact, it is also difficult to interengage the end fitting and the adapter at the level of the latter.